Kids who grow up in unsafe areas are four times more likely to be overweight than those in safer neighborhoods, a new study says.

“In attempting to protect their children from harm, parents not only decrease the kind of physical activity that comes from playing outdoors in the neighborhood, but inadvertently increase the likelihood of sedentary activity that comes from staying indoors,” said Dr. Julie Lumeng of the University of Michigan, who led the study.

Almost 16 percent of all U.S. children ages 6 to 11 are overweight.

The study is published in the Archives of Pediatrics and Adolescent Medicine.